There's a really neat premise at the heart of Damascus Gear: Operation Tokyo – a downloadable title that's destined to be completely overlooked by most. In a post-apocalyptic future where mankind's on its last legs and Japan is little more than a smouldering ruin, machines known as Rage stalk the desolate landscape, scouring forgotten cities for surviving humans in order to erase them. It's a grim future, that's for sure, but at least it gives us an opportunity to face extinction in style, taking on our Rage aggressors by piloting our own giant robots known as Gears.

Anyone who's dabbled in mecha anime or manga will have some inkling as to what's in store here. The cast is made up of Gear pilots, and the game sticks you into the story as a new recruit. Of course, it isn't long before your efforts are leading your organisation to victory against the previously unstoppable Rage, and suddenly, the future doesn't look so bleak. Truthfully, the plot could have gone further, adding more depth and context to each scenario as you work your way through several chapters, but it tends to trudge along, never really picking up pace or throwing any curve balls. It's a shame, too, because a better narrative could have sewn the six to ten hour experience up rather nicely. Instead, we're left with humdrum characters and some very minor plot twists, and it all cumulates in a tale that's less memorable than the title's dreary setting and macabre atmosphere.

Fortunately, the gameplay keeps things afloat, and honestly, there's something surprisingly special at its core. The title takes many of its cues from games like Diablo, in that as you slaughter your way through waves of foes, you'll constantly be picking up new equipment. Loot is plentiful, and with most tasks only taking a few minutes to complete, you'll be attaching new and improved parts to your Gear almost all the time. The gameplay loop that's on offer is addictive and rewarding as a result, as you gradually power up your mech with better swords, rifles, armour, and mega beam cannons.

Again, like Blizzard's loot-'em-up, Damascus Gear even opts for an isometric view point and tops things off with hack and slash combat. What we're left with is essentially a more bare bones Diablo in mecha form, and that in itself is one heck of an intriguing concept.

The groundwork's pretty solid, then, and the combat itself is fast paced and generally quite enjoyable. You choose what to have equipped in your Gear's right and left hands, and each weapon is mapped to a corresponding face button. If you're comfortable with staying at a distance and pelting Rage with bullets or lasers, grab two rifles and let loose. Likewise, if you're fresh off the Bloodborne hype train, you may want to settle for a mech that dual wields giant chainsaws and has to rely on timely dodges to survive. There are a decent amount of offensive options to experiment with, and finding a set of equipment that works for you is a rewarding process – especially if you can make good use of some of the devastating shoulder-mounted armaments.

Whatever loadout that you eventually settle upon, though, you'll always be hitting X to boost away from harm. When you get down to the nitty gritty, combat is all about timing, since your enemies are usually left wide open after attempting their own attacks. Slowly but surely, success begins to hinge on your ability to slip away from these blows and strike back, which results in battles that boast a satisfying rhythm. Factor in larger groups of foes and the need to distance yourself correctly, and there's actually an enjoyable amount of depth to explore, despite the fact that you're always limited to just a few standard techniques and little else.

Sadly, it won't be long before you're yearning for the early days, when you could carve through platoons of Rage with carefully considered but fast and effective offensives. As you progress into the tougher objectives, the game introduces enemies with increasingly meaty health bars, and sure enough, some missions devolve into tedium as you dodge and retaliate against the same predictable set of attacks over and over again. Artificial difficulty also rears its ugly head as the title later decides to flood tiny arenas with hordes of super quick foes, and huge mechs that love nothing more than to spam screen-covering cannon blasts.

All too quickly, things can fall off a cliff into a sea of total frustration, and your incomprehensibly stupid allies don't help matters. Supposedly watching your back during most missions, the supporting cast will fight alongside you in their own Gears, sporting many of the same attacks and abilities that you do. The problem, however, is that the artificial intelligence is atrocious. If they're not inexplicably wandering off in the opposite direction of your objective, they'll be standing there, motionless, as they get annihilated by projectiles from every possible angle. Needless to say, they usually don't make it to the end of a mission, and their only real use is that they'll sometimes draw fire away from you.

But the worst moments of the game – by far – are the escort missions. No, important government officials can't just take a back seat in your Gear. Instead, they jump into their own mech and casually follow your lead, even if that means strolling straight into a hive of Rage. Admittedly, it's not so bad if you're quick to wipe out encroaching enemies while managing to keep a reasonable distance between you and your client, but with bosses, you're automatically forced into a cramped space by emergency barriers, supposedly so that your opponent can't escape its destruction. On the contrary, this just means that your hapless VIP has nowhere to run, and, without an extreme case of good fortune, they'll be on the receiving end of every crushing blow that the boss deals out.

Thankfully, the game seems to acknowledge that it's going to screw you over now and again, so it does allow you to keep any loot that you've gathered up to that point when you fail an objective. Likewise, repair kits can be bought for a trivial sum of in-game currency, and you can use them at any time during any mission by tapping L. Suddenly, you'll be back to full health, meaning that you can effectively power through all of the game's content with enough repair kits on hand. Whether this is a design oversight, or a way to balance out your ridiculously crap AI buddies, we can't say.

However, every time that you shake your head in despair as another of your moronic allies bites the dust, you'll remember that you've just picked up some ultra rare loot, and you'll slog through the rest of the mission just to get to that all important equipment screen. Despite its sometimes painstakingly obvious flaws, Damascus Gear is a hard release to put down, purely because it's so good at showering you in rewards. It also helps that, as mentioned, missions tend to be short in length, which makes the whole thing feel like a perfect fit for quick, hassle-free portable play on the Vita.

Conclusion

With an undeniably cool concept at its core, Damascus Gear: Operation Tokyo is difficult to dismiss, even if its flaws will have you reaching for the self detonation device. For £7.99/$14.99, it's an enjoyable portable game with an addictive progression system, and probably worth a shot if you're a mech head – but it's still hard to look past its blatant mechanical missteps.

Robert's been a dedicated PlayStation fan since the days of Tekken 2, and he still loves a good dust up. When he's not practising combos, he's usually getting lost in the latest 100-hour RPG, or, y'know, replaying The Witcher 3.

@Bliquid There are six chapters, and each of them have varying amounts of missions - and that's all there is to it. You can replay any mission as many times as you want, but the only reason to do so is to try and track down more loot.